Randa Alfotawi
highly porous polymer matrices such as Polyethylene (PE), polyurethane, polyetheretherketone, and polysulfone. All are biocompatible polymers that are stable in the body, of which PE(MEDPOR) is the most popular which play an important role in facilitating the attachment of cells and the spread, propagation, and formation of new tissue/fluids around the bone defects. Despite the aforementioned reports of porous PE, one of the most common clinical complications1,2 associated with the use of porous PE implants is the formation of fibro-vascular ingrowth around(in form of capsule) and into it`s porous which provide late resistance to infection as documented, reaches up to 6-13 %3, 4. Aim& objectives: We proposed that, if we coat PE with calcium sulfate– hydroxylapatite (CS–HA), this would allow PE acted as an osteoconductive bone graft which enhance bone regeneration rather than formation of fibrovascularcapsule. Material &Methods: In vitro, PE disc were fabricated with pore size ranges from 100 to 400 μm, the pore volume is >35%, and the density is 0.46–0.54 g/ cm3. The calcium sulphate hydroxyapatite (CS–HA) cement was used as a thin layer coating the outer surfaces of PE disc. Human bone marrow mesenchymal stem cells were studies using cell viability assay & Scanning Electron microscopy(SEM). In vivo, the coated and non-coated PE disc were implanted at calvarial bone defects of 20 Rats. Cone beam computerized tomography(CBCT), histology, and histomorphomtery were used to assess bone regeneration inside the pores. Results: (CS–HA) coating of the scaffold not only improved attachment but also increased the proliferation of human bone marrow mesenchymal stem cells in vitro. In vivo, histological analysis showed that the coated PE`s study groups had active bone remodelling at the border of the defect. These my infer that coated polyethylene acted as an osteoconductive bone graft. Furthermore, bone formation inside the pores of the coated polyethylene was also noted, which would enhance the process of osteointegration.